/*
 * Copyright (c) 2003, 2018 Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2022 Contributors to the Eclipse Foundation
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package com.sun.jdbcra.common;

import com.sun.jdbcra.util.MethodExecutor;

import jakarta.resource.ResourceException;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.StringTokenizer;
import java.util.Vector;
/**
 * Utility class, which would create necessary Datasource object according to the
 * specification.
 *
 * @version        1.0, 02/07/23
 * @author        Binod P.G
 * @see                com.sun.jdbcra.common.DataSourceSpec
 * @see                com.sun.jdbcra.util.MethodExecutor
 */
public class DataSourceObjectBuilder implements java.io.Serializable{

    private final DataSourceSpec spec;
    private final MethodExecutor executor;
    private Hashtable driverProperties;


    /**
     * Construct a DataSource Object from the spec.
     *
     * @param        spec        <code> DataSourceSpec </code> object.
     */
    public DataSourceObjectBuilder(DataSourceSpec spec) {
            this.spec = spec;
            executor = new MethodExecutor();
    }

    /**
     * Construct the DataSource Object from the spec.
     *
     * @return        Object constructed using the DataSourceSpec.
     * @throws        <code>ResourceException</code> if the class is not found or some issue in executing
     *                some method.
     */
    public Object constructDataSourceObject() throws ResourceException{
        driverProperties = parseDriverProperties(spec);
        Object dataSourceObject = getDataSourceObject();
        Method[] methods = dataSourceObject.getClass().getMethods();
        for (Method method : methods) {
            String methodName = method.getName();
            if (methodName.equalsIgnoreCase("setUser")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.USERNAME),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setPassword")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.PASSWORD),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setLoginTimeOut")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.LOGINTIMEOUT),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setLogWriter")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.LOGWRITER),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setDatabaseName")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.DATABASENAME),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setDataSourceName")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.DATASOURCENAME),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setDescription")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.DESCRIPTION),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setNetworkProtocol")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.NETWORKPROTOCOL),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setPortNumber")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.PORTNUMBER),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setRoleName")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.ROLENAME),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setServerName")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.SERVERNAME),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setMaxStatements")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.MAXSTATEMENTS),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setInitialPoolSize")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.INITIALPOOLSIZE),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setMinPoolSize")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.MINPOOLSIZE),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setMaxPoolSize")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.MAXPOOLSIZE),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setMaxIdleTime")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.MAXIDLETIME),method,dataSourceObject);

            } else if (methodName.equalsIgnoreCase("setPropertyCycle")){
                    executor.runJavaBeanMethod(spec.getDetail(DataSourceSpec.PROPERTYCYCLE),method,dataSourceObject);

            } else if (driverProperties.containsKey(methodName.toUpperCase())){
                    Vector values = (Vector) driverProperties.get(methodName.toUpperCase());
                executor.runMethod(method,dataSourceObject, values);
            }
        }
        return dataSourceObject;
    }

    /**
     * Get the extra driver properties from the DataSourceSpec object and
     * parse them to a set of methodName and parameters. Prepare a hashtable
     * containing these details and return.
     *
     * @param        spec        <code> DataSourceSpec </code> object.
     * @return        Hashtable containing method names and parameters,
     * @throws        ResourceException        If delimiter is not provided and property string
     *                                        is not null.
     */
    private Hashtable parseDriverProperties(DataSourceSpec spec) throws ResourceException {
        String delim = spec.getDetail(DataSourceSpec.DELIMITER);

        String prop = spec.getDetail(DataSourceSpec.DRIVERPROPERTIES);
        if (prop == null || prop.trim().equals("")) {
            return new Hashtable();
        } else if (delim == null || delim.equals("")) {
            throw new ResourceException("Delimiter is not provided in the configuration");
        }

        Hashtable properties = new Hashtable();
        delim = delim.trim();
        String sep = delim + delim;
        int sepLen = sep.length();
        String cache = prop;
        Vector methods = new Vector();

        while (cache.indexOf(sep) != -1) {
            int index = cache.indexOf(sep);
            String name = cache.substring(0, index);
            if (name.trim() != "") {
                methods.add(name);
                cache = cache.substring(index + sepLen);
            }
        }

        Enumeration allMethods = methods.elements();
        while (allMethods.hasMoreElements()) {
            String oneMethod = (String) allMethods.nextElement();
            if (!oneMethod.trim().equals("")) {
                String methodName = null;
                Vector parms = new Vector();
                StringTokenizer methodDetails = new StringTokenizer(oneMethod, delim);
                for (int i = 0; methodDetails.hasMoreTokens(); i++) {
                    String token = methodDetails.nextToken();
                    if (i == 0) {
                        methodName = token.toUpperCase();
                    } else {
                        parms.add(token);
                    }
                }
                properties.put(methodName, parms);
            }
        }
        return properties;
    }


    /**
     * Creates a Datasource object according to the spec.
     *
     * @return Initial DataSource Object instance.
     * @throws <code>ResourceException</code> If class name is wrong or classpath is not set
     * properly.
     */
    private Object getDataSourceObject() throws ResourceException{
        String className = spec.getDetail(DataSourceSpec.CLASSNAME);
        try {
            Class<?> dataSourceClass = Class.forName(className);
            return dataSourceClass.getDeclaredConstructor().newInstance();
        } catch(ClassNotFoundException cfne){
            throw new ResourceException("Class Name is wrong or Class path is not set for :" + className, cfne);
        } catch(InstantiationException | InvocationTargetException | NoSuchMethodException ce) {
            throw new ResourceException("Error in instantiating" + className, ce);
        } catch(IllegalAccessException ce) {
            throw new ResourceException("Access Error in instantiating" + className, ce);
        }
    }

}